What are common signs of intoxication that servers should observe?

B is the most appropriate choice because slurred speech, stumbling, and impaired judgment are well-known indicators of intoxication. These signs reflect the physical and cognitive impairments caused by alcohol consumption. For instance, when someone has slurred speech, it indicates a lack of coordination and control over their speech muscles, which is often a result of alcohol affecting the brain's functioning. Stumbling suggests a lack of balance and motor coordination, while impaired judgment can lead to poor decision-making, which servers must be vigilant about to ensure the safety of all patrons.

In contrast, the other options present characteristics that do not typically correlate with intoxication. For example, clear speech and steady walking indicate that an individual is likely sober and in control of their faculties. Cheerful behavior and excessive talking could be normal social interactions and do not definitively indicate a level of intoxication. Lastly, a silent and calm demeanor may suggest a person is simply reserved or not engaging, but it could also be misleading since these traits do not directly signal impairment either. Recognizing actual signs of intoxication is essential for servers to responsibly manage alcohol service and maintain a safe environment.